1124 lines
		
	
	
		
			33 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1124 lines
		
	
	
		
			33 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/**
 | 
						|
 * eCryptfs: Linux filesystem encryption layer
 | 
						|
 *
 | 
						|
 * Copyright (C) 1997-2004 Erez Zadok
 | 
						|
 * Copyright (C) 2001-2004 Stony Brook University
 | 
						|
 * Copyright (C) 2004-2007 International Business Machines Corp.
 | 
						|
 *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
 | 
						|
 *              Michael C. Thompsion <mcthomps@us.ibm.com>
 | 
						|
 *
 | 
						|
 * This program is free software; you can redistribute it and/or
 | 
						|
 * modify it under the terms of the GNU General Public License as
 | 
						|
 * published by the Free Software Foundation; either version 2 of the
 | 
						|
 * License, or (at your option) any later version.
 | 
						|
 *
 | 
						|
 * This program is distributed in the hope that it will be useful, but
 | 
						|
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | 
						|
 * General Public License for more details.
 | 
						|
 *
 | 
						|
 * You should have received a copy of the GNU General Public License
 | 
						|
 * along with this program; if not, write to the Free Software
 | 
						|
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 | 
						|
 * 02111-1307, USA.
 | 
						|
 */
 | 
						|
 | 
						|
#include <linux/file.h>
 | 
						|
#include <linux/vmalloc.h>
 | 
						|
#include <linux/pagemap.h>
 | 
						|
#include <linux/dcache.h>
 | 
						|
#include <linux/namei.h>
 | 
						|
#include <linux/mount.h>
 | 
						|
#include <linux/crypto.h>
 | 
						|
#include <linux/fs_stack.h>
 | 
						|
#include <asm/unaligned.h>
 | 
						|
#include "ecryptfs_kernel.h"
 | 
						|
 | 
						|
static struct dentry *lock_parent(struct dentry *dentry)
 | 
						|
{
 | 
						|
	struct dentry *dir;
 | 
						|
 | 
						|
	dir = dget_parent(dentry);
 | 
						|
	mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT);
 | 
						|
	return dir;
 | 
						|
}
 | 
						|
 | 
						|
static void unlock_dir(struct dentry *dir)
 | 
						|
{
 | 
						|
	mutex_unlock(&dir->d_inode->i_mutex);
 | 
						|
	dput(dir);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * ecryptfs_create_underlying_file
 | 
						|
 * @lower_dir_inode: inode of the parent in the lower fs of the new file
 | 
						|
 * @dentry: New file's dentry
 | 
						|
 * @mode: The mode of the new file
 | 
						|
 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
 | 
						|
 *
 | 
						|
 * Creates the file in the lower file system.
 | 
						|
 *
 | 
						|
 * Returns zero on success; non-zero on error condition
 | 
						|
 */
 | 
						|
static int
 | 
						|
ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
 | 
						|
				struct dentry *dentry, int mode,
 | 
						|
				struct nameidata *nd)
 | 
						|
{
 | 
						|
	struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
 | 
						|
	struct dentry *dentry_save;
 | 
						|
	struct vfsmount *vfsmount_save;
 | 
						|
	int rc;
 | 
						|
 | 
						|
	dentry_save = nd->path.dentry;
 | 
						|
	vfsmount_save = nd->path.mnt;
 | 
						|
	nd->path.dentry = lower_dentry;
 | 
						|
	nd->path.mnt = lower_mnt;
 | 
						|
	rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
 | 
						|
	nd->path.dentry = dentry_save;
 | 
						|
	nd->path.mnt = vfsmount_save;
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * ecryptfs_do_create
 | 
						|
 * @directory_inode: inode of the new file's dentry's parent in ecryptfs
 | 
						|
 * @ecryptfs_dentry: New file's dentry in ecryptfs
 | 
						|
 * @mode: The mode of the new file
 | 
						|
 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
 | 
						|
 *
 | 
						|
 * Creates the underlying file and the eCryptfs inode which will link to
 | 
						|
 * it. It will also update the eCryptfs directory inode to mimic the
 | 
						|
 * stat of the lower directory inode.
 | 
						|
 *
 | 
						|
 * Returns zero on success; non-zero on error condition
 | 
						|
 */
 | 
						|
static int
 | 
						|
ecryptfs_do_create(struct inode *directory_inode,
 | 
						|
		   struct dentry *ecryptfs_dentry, int mode,
 | 
						|
		   struct nameidata *nd)
 | 
						|
{
 | 
						|
	int rc;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
	struct dentry *lower_dir_dentry;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
 | 
						|
	lower_dir_dentry = lock_parent(lower_dentry);
 | 
						|
	if (IS_ERR(lower_dir_dentry)) {
 | 
						|
		ecryptfs_printk(KERN_ERR, "Error locking directory of "
 | 
						|
				"dentry\n");
 | 
						|
		rc = PTR_ERR(lower_dir_dentry);
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
 | 
						|
					     ecryptfs_dentry, mode, nd);
 | 
						|
	if (rc) {
 | 
						|
		printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
 | 
						|
		       "rc = [%d]\n", __func__, rc);
 | 
						|
		goto out_lock;
 | 
						|
	}
 | 
						|
	rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
 | 
						|
				directory_inode->i_sb, 0);
 | 
						|
	if (rc) {
 | 
						|
		ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
 | 
						|
		goto out_lock;
 | 
						|
	}
 | 
						|
	fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
 | 
						|
	fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
 | 
						|
out_lock:
 | 
						|
	unlock_dir(lower_dir_dentry);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * grow_file
 | 
						|
 * @ecryptfs_dentry: the eCryptfs dentry
 | 
						|
 *
 | 
						|
 * This is the code which will grow the file to its correct size.
 | 
						|
 */
 | 
						|
static int grow_file(struct dentry *ecryptfs_dentry)
 | 
						|
{
 | 
						|
	struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
 | 
						|
	struct file fake_file;
 | 
						|
	struct ecryptfs_file_info tmp_file_info;
 | 
						|
	char zero_virt[] = { 0x00 };
 | 
						|
	int rc = 0;
 | 
						|
 | 
						|
	memset(&fake_file, 0, sizeof(fake_file));
 | 
						|
	fake_file.f_path.dentry = ecryptfs_dentry;
 | 
						|
	memset(&tmp_file_info, 0, sizeof(tmp_file_info));
 | 
						|
	ecryptfs_set_file_private(&fake_file, &tmp_file_info);
 | 
						|
	ecryptfs_set_file_lower(
 | 
						|
		&fake_file,
 | 
						|
		ecryptfs_inode_to_private(ecryptfs_inode)->lower_file);
 | 
						|
	rc = ecryptfs_write(&fake_file, zero_virt, 0, 1);
 | 
						|
	i_size_write(ecryptfs_inode, 0);
 | 
						|
	rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
 | 
						|
	ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |=
 | 
						|
		ECRYPTFS_NEW_FILE;
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * ecryptfs_initialize_file
 | 
						|
 *
 | 
						|
 * Cause the file to be changed from a basic empty file to an ecryptfs
 | 
						|
 * file with a header and first data page.
 | 
						|
 *
 | 
						|
 * Returns zero on success
 | 
						|
 */
 | 
						|
static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
 | 
						|
{
 | 
						|
	struct ecryptfs_crypt_stat *crypt_stat =
 | 
						|
		&ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
 | 
						|
	int rc = 0;
 | 
						|
 | 
						|
	if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
 | 
						|
		ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
 | 
						|
		crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	crypt_stat->flags |= ECRYPTFS_NEW_FILE;
 | 
						|
	ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
 | 
						|
	rc = ecryptfs_new_file_context(ecryptfs_dentry);
 | 
						|
	if (rc) {
 | 
						|
		ecryptfs_printk(KERN_ERR, "Error creating new file "
 | 
						|
				"context; rc = [%d]\n", rc);
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
 | 
						|
		rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
 | 
						|
		if (rc) {
 | 
						|
			printk(KERN_ERR "%s: Error attempting to initialize "
 | 
						|
			       "the persistent file for the dentry with name "
 | 
						|
			       "[%s]; rc = [%d]\n", __func__,
 | 
						|
			       ecryptfs_dentry->d_name.name, rc);
 | 
						|
			goto out;
 | 
						|
		}
 | 
						|
	}
 | 
						|
	rc = ecryptfs_write_metadata(ecryptfs_dentry);
 | 
						|
	if (rc) {
 | 
						|
		printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	rc = grow_file(ecryptfs_dentry);
 | 
						|
	if (rc)
 | 
						|
		printk(KERN_ERR "Error growing file; rc = [%d]\n", rc);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * ecryptfs_create
 | 
						|
 * @dir: The inode of the directory in which to create the file.
 | 
						|
 * @dentry: The eCryptfs dentry
 | 
						|
 * @mode: The mode of the new file.
 | 
						|
 * @nd: nameidata
 | 
						|
 *
 | 
						|
 * Creates a new file.
 | 
						|
 *
 | 
						|
 * Returns zero on success; non-zero on error condition
 | 
						|
 */
 | 
						|
static int
 | 
						|
ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
 | 
						|
		int mode, struct nameidata *nd)
 | 
						|
{
 | 
						|
	int rc;
 | 
						|
 | 
						|
	/* ecryptfs_do_create() calls ecryptfs_interpose() */
 | 
						|
	rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
 | 
						|
	if (unlikely(rc)) {
 | 
						|
		ecryptfs_printk(KERN_WARNING, "Failed to create file in"
 | 
						|
				"lower filesystem\n");
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	/* At this point, a file exists on "disk"; we need to make sure
 | 
						|
	 * that this on disk file is prepared to be an ecryptfs file */
 | 
						|
	rc = ecryptfs_initialize_file(ecryptfs_dentry);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * ecryptfs_lookup_and_interpose_lower - Perform a lookup
 | 
						|
 */
 | 
						|
int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
 | 
						|
					struct dentry *lower_dentry,
 | 
						|
					struct inode *ecryptfs_dir_inode,
 | 
						|
					struct nameidata *ecryptfs_nd)
 | 
						|
{
 | 
						|
	struct dentry *lower_dir_dentry;
 | 
						|
	struct vfsmount *lower_mnt;
 | 
						|
	struct inode *lower_inode;
 | 
						|
	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 | 
						|
	struct ecryptfs_crypt_stat *crypt_stat;
 | 
						|
	char *page_virt = NULL;
 | 
						|
	u64 file_size;
 | 
						|
	int rc = 0;
 | 
						|
 | 
						|
	lower_dir_dentry = lower_dentry->d_parent;
 | 
						|
	lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
 | 
						|
				   ecryptfs_dentry->d_parent));
 | 
						|
	lower_inode = lower_dentry->d_inode;
 | 
						|
	fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode);
 | 
						|
	BUG_ON(!atomic_read(&lower_dentry->d_count));
 | 
						|
	ecryptfs_set_dentry_private(ecryptfs_dentry,
 | 
						|
				    kmem_cache_alloc(ecryptfs_dentry_info_cache,
 | 
						|
						     GFP_KERNEL));
 | 
						|
	if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) {
 | 
						|
		rc = -ENOMEM;
 | 
						|
		printk(KERN_ERR "%s: Out of memory whilst attempting "
 | 
						|
		       "to allocate ecryptfs_dentry_info struct\n",
 | 
						|
			__func__);
 | 
						|
		goto out_dput;
 | 
						|
	}
 | 
						|
	ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry);
 | 
						|
	ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt);
 | 
						|
	if (!lower_dentry->d_inode) {
 | 
						|
		/* We want to add because we couldn't find in lower */
 | 
						|
		d_add(ecryptfs_dentry, NULL);
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
 | 
						|
				ecryptfs_dir_inode->i_sb, 1);
 | 
						|
	if (rc) {
 | 
						|
		printk(KERN_ERR "%s: Error interposing; rc = [%d]\n",
 | 
						|
		       __func__, rc);
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	if (S_ISDIR(lower_inode->i_mode))
 | 
						|
		goto out;
 | 
						|
	if (S_ISLNK(lower_inode->i_mode))
 | 
						|
		goto out;
 | 
						|
	if (special_file(lower_inode->i_mode))
 | 
						|
		goto out;
 | 
						|
	if (!ecryptfs_nd)
 | 
						|
		goto out;
 | 
						|
	/* Released in this function */
 | 
						|
	page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER);
 | 
						|
	if (!page_virt) {
 | 
						|
		printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n",
 | 
						|
		       __func__);
 | 
						|
		rc = -ENOMEM;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
 | 
						|
		rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
 | 
						|
		if (rc) {
 | 
						|
			printk(KERN_ERR "%s: Error attempting to initialize "
 | 
						|
			       "the persistent file for the dentry with name "
 | 
						|
			       "[%s]; rc = [%d]\n", __func__,
 | 
						|
			       ecryptfs_dentry->d_name.name, rc);
 | 
						|
			goto out_free_kmem;
 | 
						|
		}
 | 
						|
	}
 | 
						|
	crypt_stat = &ecryptfs_inode_to_private(
 | 
						|
					ecryptfs_dentry->d_inode)->crypt_stat;
 | 
						|
	/* TODO: lock for crypt_stat comparison */
 | 
						|
	if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
 | 
						|
			ecryptfs_set_default_sizes(crypt_stat);
 | 
						|
	rc = ecryptfs_read_and_validate_header_region(page_virt,
 | 
						|
						      ecryptfs_dentry->d_inode);
 | 
						|
	if (rc) {
 | 
						|
		rc = ecryptfs_read_and_validate_xattr_region(page_virt,
 | 
						|
							     ecryptfs_dentry);
 | 
						|
		if (rc) {
 | 
						|
			rc = 0;
 | 
						|
			goto out_free_kmem;
 | 
						|
		}
 | 
						|
		crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
 | 
						|
	}
 | 
						|
	mount_crypt_stat = &ecryptfs_superblock_to_private(
 | 
						|
		ecryptfs_dentry->d_sb)->mount_crypt_stat;
 | 
						|
	if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
 | 
						|
		if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
 | 
						|
			file_size = (crypt_stat->num_header_bytes_at_front
 | 
						|
				     + i_size_read(lower_dentry->d_inode));
 | 
						|
		else
 | 
						|
			file_size = i_size_read(lower_dentry->d_inode);
 | 
						|
	} else {
 | 
						|
		file_size = get_unaligned_be64(page_virt);
 | 
						|
	}
 | 
						|
	i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size);
 | 
						|
out_free_kmem:
 | 
						|
	kmem_cache_free(ecryptfs_header_cache_2, page_virt);
 | 
						|
	goto out;
 | 
						|
out_dput:
 | 
						|
	dput(lower_dentry);
 | 
						|
	d_drop(ecryptfs_dentry);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * ecryptfs_lookup
 | 
						|
 * @ecryptfs_dir_inode: The eCryptfs directory inode
 | 
						|
 * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
 | 
						|
 * @ecryptfs_nd: nameidata; may be NULL
 | 
						|
 *
 | 
						|
 * Find a file on disk. If the file does not exist, then we'll add it to the
 | 
						|
 * dentry cache and continue on to read it from the disk.
 | 
						|
 */
 | 
						|
static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
 | 
						|
				      struct dentry *ecryptfs_dentry,
 | 
						|
				      struct nameidata *ecryptfs_nd)
 | 
						|
{
 | 
						|
	char *encrypted_and_encoded_name = NULL;
 | 
						|
	size_t encrypted_and_encoded_name_size;
 | 
						|
	struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
 | 
						|
	struct dentry *lower_dir_dentry, *lower_dentry;
 | 
						|
	int rc = 0;
 | 
						|
 | 
						|
	ecryptfs_dentry->d_op = &ecryptfs_dops;
 | 
						|
	if ((ecryptfs_dentry->d_name.len == 1
 | 
						|
	     && !strcmp(ecryptfs_dentry->d_name.name, "."))
 | 
						|
	    || (ecryptfs_dentry->d_name.len == 2
 | 
						|
		&& !strcmp(ecryptfs_dentry->d_name.name, ".."))) {
 | 
						|
		goto out_d_drop;
 | 
						|
	}
 | 
						|
	lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
 | 
						|
	mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
 | 
						|
	lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,
 | 
						|
				      lower_dir_dentry,
 | 
						|
				      ecryptfs_dentry->d_name.len);
 | 
						|
	mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
 | 
						|
	if (IS_ERR(lower_dentry)) {
 | 
						|
		rc = PTR_ERR(lower_dentry);
 | 
						|
		printk(KERN_ERR "%s: lookup_one_len() returned [%d] on "
 | 
						|
		       "lower_dentry = [%s]\n", __func__, rc,
 | 
						|
		       ecryptfs_dentry->d_name.name);
 | 
						|
		goto out_d_drop;
 | 
						|
	}
 | 
						|
	if (lower_dentry->d_inode)
 | 
						|
		goto lookup_and_interpose;
 | 
						|
	mount_crypt_stat = &ecryptfs_superblock_to_private(
 | 
						|
				ecryptfs_dentry->d_sb)->mount_crypt_stat;
 | 
						|
	if (!(mount_crypt_stat
 | 
						|
	    && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
 | 
						|
		goto lookup_and_interpose;
 | 
						|
	dput(lower_dentry);
 | 
						|
	rc = ecryptfs_encrypt_and_encode_filename(
 | 
						|
		&encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
 | 
						|
		NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name,
 | 
						|
		ecryptfs_dentry->d_name.len);
 | 
						|
	if (rc) {
 | 
						|
		printk(KERN_ERR "%s: Error attempting to encrypt and encode "
 | 
						|
		       "filename; rc = [%d]\n", __func__, rc);
 | 
						|
		goto out_d_drop;
 | 
						|
	}
 | 
						|
	mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
 | 
						|
	lower_dentry = lookup_one_len(encrypted_and_encoded_name,
 | 
						|
				      lower_dir_dentry,
 | 
						|
				      encrypted_and_encoded_name_size - 1);
 | 
						|
	mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
 | 
						|
	if (IS_ERR(lower_dentry)) {
 | 
						|
		rc = PTR_ERR(lower_dentry);
 | 
						|
		printk(KERN_ERR "%s: lookup_one_len() returned [%d] on "
 | 
						|
		       "lower_dentry = [%s]\n", __func__, rc,
 | 
						|
		       encrypted_and_encoded_name);
 | 
						|
		goto out_d_drop;
 | 
						|
	}
 | 
						|
lookup_and_interpose:
 | 
						|
	rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry,
 | 
						|
						 ecryptfs_dir_inode,
 | 
						|
						 ecryptfs_nd);
 | 
						|
	goto out;
 | 
						|
out_d_drop:
 | 
						|
	d_drop(ecryptfs_dentry);
 | 
						|
out:
 | 
						|
	kfree(encrypted_and_encoded_name);
 | 
						|
	return ERR_PTR(rc);
 | 
						|
}
 | 
						|
 | 
						|
static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
 | 
						|
			 struct dentry *new_dentry)
 | 
						|
{
 | 
						|
	struct dentry *lower_old_dentry;
 | 
						|
	struct dentry *lower_new_dentry;
 | 
						|
	struct dentry *lower_dir_dentry;
 | 
						|
	u64 file_size_save;
 | 
						|
	int rc;
 | 
						|
 | 
						|
	file_size_save = i_size_read(old_dentry->d_inode);
 | 
						|
	lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
 | 
						|
	lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 | 
						|
	dget(lower_old_dentry);
 | 
						|
	dget(lower_new_dentry);
 | 
						|
	lower_dir_dentry = lock_parent(lower_new_dentry);
 | 
						|
	rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
 | 
						|
		      lower_new_dentry);
 | 
						|
	if (rc || !lower_new_dentry->d_inode)
 | 
						|
		goto out_lock;
 | 
						|
	rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
 | 
						|
	if (rc)
 | 
						|
		goto out_lock;
 | 
						|
	fsstack_copy_attr_times(dir, lower_new_dentry->d_inode);
 | 
						|
	fsstack_copy_inode_size(dir, lower_new_dentry->d_inode);
 | 
						|
	old_dentry->d_inode->i_nlink =
 | 
						|
		ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
 | 
						|
	i_size_write(new_dentry->d_inode, file_size_save);
 | 
						|
out_lock:
 | 
						|
	unlock_dir(lower_dir_dentry);
 | 
						|
	dput(lower_new_dentry);
 | 
						|
	dput(lower_old_dentry);
 | 
						|
	d_drop(lower_old_dentry);
 | 
						|
	d_drop(new_dentry);
 | 
						|
	d_drop(old_dentry);
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
 | 
						|
{
 | 
						|
	int rc = 0;
 | 
						|
	struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
 | 
						|
	struct dentry *lower_dir_dentry;
 | 
						|
 | 
						|
	dget(lower_dentry);
 | 
						|
	lower_dir_dentry = lock_parent(lower_dentry);
 | 
						|
	rc = vfs_unlink(lower_dir_inode, lower_dentry);
 | 
						|
	if (rc) {
 | 
						|
		printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
 | 
						|
		goto out_unlock;
 | 
						|
	}
 | 
						|
	fsstack_copy_attr_times(dir, lower_dir_inode);
 | 
						|
	dentry->d_inode->i_nlink =
 | 
						|
		ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
 | 
						|
	dentry->d_inode->i_ctime = dir->i_ctime;
 | 
						|
	d_drop(dentry);
 | 
						|
out_unlock:
 | 
						|
	unlock_dir(lower_dir_dentry);
 | 
						|
	dput(lower_dentry);
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
 | 
						|
			    const char *symname)
 | 
						|
{
 | 
						|
	int rc;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
	struct dentry *lower_dir_dentry;
 | 
						|
	char *encoded_symname;
 | 
						|
	size_t encoded_symlen;
 | 
						|
	struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	dget(lower_dentry);
 | 
						|
	lower_dir_dentry = lock_parent(lower_dentry);
 | 
						|
	mount_crypt_stat = &ecryptfs_superblock_to_private(
 | 
						|
		dir->i_sb)->mount_crypt_stat;
 | 
						|
	rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
 | 
						|
						  &encoded_symlen,
 | 
						|
						  NULL,
 | 
						|
						  mount_crypt_stat, symname,
 | 
						|
						  strlen(symname));
 | 
						|
	if (rc)
 | 
						|
		goto out_lock;
 | 
						|
	rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
 | 
						|
			 encoded_symname);
 | 
						|
	kfree(encoded_symname);
 | 
						|
	if (rc || !lower_dentry->d_inode)
 | 
						|
		goto out_lock;
 | 
						|
	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 | 
						|
	if (rc)
 | 
						|
		goto out_lock;
 | 
						|
	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 | 
						|
	fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 | 
						|
out_lock:
 | 
						|
	unlock_dir(lower_dir_dentry);
 | 
						|
	dput(lower_dentry);
 | 
						|
	if (!dentry->d_inode)
 | 
						|
		d_drop(dentry);
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 | 
						|
{
 | 
						|
	int rc;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
	struct dentry *lower_dir_dentry;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	lower_dir_dentry = lock_parent(lower_dentry);
 | 
						|
	rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
 | 
						|
	if (rc || !lower_dentry->d_inode)
 | 
						|
		goto out;
 | 
						|
	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 | 
						|
	if (rc)
 | 
						|
		goto out;
 | 
						|
	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 | 
						|
	fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 | 
						|
	dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
 | 
						|
out:
 | 
						|
	unlock_dir(lower_dir_dentry);
 | 
						|
	if (!dentry->d_inode)
 | 
						|
		d_drop(dentry);
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
 | 
						|
{
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
	struct dentry *lower_dir_dentry;
 | 
						|
	int rc;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	dget(dentry);
 | 
						|
	lower_dir_dentry = lock_parent(lower_dentry);
 | 
						|
	dget(lower_dentry);
 | 
						|
	rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
 | 
						|
	dput(lower_dentry);
 | 
						|
	if (!rc)
 | 
						|
		d_delete(lower_dentry);
 | 
						|
	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 | 
						|
	dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
 | 
						|
	unlock_dir(lower_dir_dentry);
 | 
						|
	if (!rc)
 | 
						|
		d_drop(dentry);
 | 
						|
	dput(dentry);
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
 | 
						|
{
 | 
						|
	int rc;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
	struct dentry *lower_dir_dentry;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	lower_dir_dentry = lock_parent(lower_dentry);
 | 
						|
	rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
 | 
						|
	if (rc || !lower_dentry->d_inode)
 | 
						|
		goto out;
 | 
						|
	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 | 
						|
	if (rc)
 | 
						|
		goto out;
 | 
						|
	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 | 
						|
	fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 | 
						|
out:
 | 
						|
	unlock_dir(lower_dir_dentry);
 | 
						|
	if (!dentry->d_inode)
 | 
						|
		d_drop(dentry);
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 | 
						|
		struct inode *new_dir, struct dentry *new_dentry)
 | 
						|
{
 | 
						|
	int rc;
 | 
						|
	struct dentry *lower_old_dentry;
 | 
						|
	struct dentry *lower_new_dentry;
 | 
						|
	struct dentry *lower_old_dir_dentry;
 | 
						|
	struct dentry *lower_new_dir_dentry;
 | 
						|
 | 
						|
	lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
 | 
						|
	lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 | 
						|
	dget(lower_old_dentry);
 | 
						|
	dget(lower_new_dentry);
 | 
						|
	lower_old_dir_dentry = dget_parent(lower_old_dentry);
 | 
						|
	lower_new_dir_dentry = dget_parent(lower_new_dentry);
 | 
						|
	lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
 | 
						|
	rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
 | 
						|
			lower_new_dir_dentry->d_inode, lower_new_dentry);
 | 
						|
	if (rc)
 | 
						|
		goto out_lock;
 | 
						|
	fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode, NULL);
 | 
						|
	if (new_dir != old_dir)
 | 
						|
		fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode, NULL);
 | 
						|
out_lock:
 | 
						|
	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
 | 
						|
	dput(lower_new_dentry->d_parent);
 | 
						|
	dput(lower_old_dentry->d_parent);
 | 
						|
	dput(lower_new_dentry);
 | 
						|
	dput(lower_old_dentry);
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
 | 
						|
{
 | 
						|
	char *lower_buf;
 | 
						|
	size_t lower_bufsiz;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 | 
						|
	char *plaintext_name;
 | 
						|
	size_t plaintext_name_size;
 | 
						|
	mm_segment_t old_fs;
 | 
						|
	int rc;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	if (!lower_dentry->d_inode->i_op->readlink) {
 | 
						|
		rc = -EINVAL;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	mount_crypt_stat = &ecryptfs_superblock_to_private(
 | 
						|
						dentry->d_sb)->mount_crypt_stat;
 | 
						|
	/*
 | 
						|
	 * If the lower filename is encrypted, it will result in a significantly
 | 
						|
	 * longer name.  If needed, truncate the name after decode and decrypt.
 | 
						|
	 */
 | 
						|
	if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
 | 
						|
		lower_bufsiz = PATH_MAX;
 | 
						|
	else
 | 
						|
		lower_bufsiz = bufsiz;
 | 
						|
	/* Released in this function */
 | 
						|
	lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
 | 
						|
	if (lower_buf == NULL) {
 | 
						|
		printk(KERN_ERR "%s: Out of memory whilst attempting to "
 | 
						|
		       "kmalloc [%zd] bytes\n", __func__, lower_bufsiz);
 | 
						|
		rc = -ENOMEM;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	old_fs = get_fs();
 | 
						|
	set_fs(get_ds());
 | 
						|
	rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
 | 
						|
						   (char __user *)lower_buf,
 | 
						|
						   lower_bufsiz);
 | 
						|
	set_fs(old_fs);
 | 
						|
	if (rc >= 0) {
 | 
						|
		rc = ecryptfs_decode_and_decrypt_filename(&plaintext_name,
 | 
						|
							  &plaintext_name_size,
 | 
						|
							  dentry, lower_buf,
 | 
						|
							  rc);
 | 
						|
		if (rc) {
 | 
						|
			printk(KERN_ERR "%s: Error attempting to decode and "
 | 
						|
			       "decrypt filename; rc = [%d]\n", __func__,
 | 
						|
				rc);
 | 
						|
			goto out_free_lower_buf;
 | 
						|
		}
 | 
						|
		/* Check for bufsiz <= 0 done in sys_readlinkat() */
 | 
						|
		rc = copy_to_user(buf, plaintext_name,
 | 
						|
				  min((size_t) bufsiz, plaintext_name_size));
 | 
						|
		if (rc)
 | 
						|
			rc = -EFAULT;
 | 
						|
		else
 | 
						|
			rc = plaintext_name_size;
 | 
						|
		kfree(plaintext_name);
 | 
						|
		fsstack_copy_attr_atime(dentry->d_inode, lower_dentry->d_inode);
 | 
						|
	}
 | 
						|
out_free_lower_buf:
 | 
						|
	kfree(lower_buf);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 | 
						|
{
 | 
						|
	char *buf;
 | 
						|
	int len = PAGE_SIZE, rc;
 | 
						|
	mm_segment_t old_fs;
 | 
						|
 | 
						|
	/* Released in ecryptfs_put_link(); only release here on error */
 | 
						|
	buf = kmalloc(len, GFP_KERNEL);
 | 
						|
	if (!buf) {
 | 
						|
		rc = -ENOMEM;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	old_fs = get_fs();
 | 
						|
	set_fs(get_ds());
 | 
						|
	rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
 | 
						|
	set_fs(old_fs);
 | 
						|
	if (rc < 0)
 | 
						|
		goto out_free;
 | 
						|
	else
 | 
						|
		buf[rc] = '\0';
 | 
						|
	rc = 0;
 | 
						|
	nd_set_link(nd, buf);
 | 
						|
	goto out;
 | 
						|
out_free:
 | 
						|
	kfree(buf);
 | 
						|
out:
 | 
						|
	return ERR_PTR(rc);
 | 
						|
}
 | 
						|
 | 
						|
static void
 | 
						|
ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
 | 
						|
{
 | 
						|
	/* Free the char* */
 | 
						|
	kfree(nd_get_link(nd));
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * upper_size_to_lower_size
 | 
						|
 * @crypt_stat: Crypt_stat associated with file
 | 
						|
 * @upper_size: Size of the upper file
 | 
						|
 *
 | 
						|
 * Calculate the required size of the lower file based on the
 | 
						|
 * specified size of the upper file. This calculation is based on the
 | 
						|
 * number of headers in the underlying file and the extent size.
 | 
						|
 *
 | 
						|
 * Returns Calculated size of the lower file.
 | 
						|
 */
 | 
						|
static loff_t
 | 
						|
upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
 | 
						|
			 loff_t upper_size)
 | 
						|
{
 | 
						|
	loff_t lower_size;
 | 
						|
 | 
						|
	lower_size = crypt_stat->num_header_bytes_at_front;
 | 
						|
	if (upper_size != 0) {
 | 
						|
		loff_t num_extents;
 | 
						|
 | 
						|
		num_extents = upper_size >> crypt_stat->extent_shift;
 | 
						|
		if (upper_size & ~crypt_stat->extent_mask)
 | 
						|
			num_extents++;
 | 
						|
		lower_size += (num_extents * crypt_stat->extent_size);
 | 
						|
	}
 | 
						|
	return lower_size;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * ecryptfs_truncate
 | 
						|
 * @dentry: The ecryptfs layer dentry
 | 
						|
 * @new_length: The length to expand the file to
 | 
						|
 *
 | 
						|
 * Function to handle truncations modifying the size of the file. Note
 | 
						|
 * that the file sizes are interpolated. When expanding, we are simply
 | 
						|
 * writing strings of 0's out. When truncating, we need to modify the
 | 
						|
 * underlying file size according to the page index interpolations.
 | 
						|
 *
 | 
						|
 * Returns zero on success; non-zero otherwise
 | 
						|
 */
 | 
						|
int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
 | 
						|
{
 | 
						|
	int rc = 0;
 | 
						|
	struct inode *inode = dentry->d_inode;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
	struct file fake_ecryptfs_file;
 | 
						|
	struct ecryptfs_crypt_stat *crypt_stat;
 | 
						|
	loff_t i_size = i_size_read(inode);
 | 
						|
	loff_t lower_size_before_truncate;
 | 
						|
	loff_t lower_size_after_truncate;
 | 
						|
 | 
						|
	if (unlikely((new_length == i_size)))
 | 
						|
		goto out;
 | 
						|
	crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
 | 
						|
	/* Set up a fake ecryptfs file, this is used to interface with
 | 
						|
	 * the file in the underlying filesystem so that the
 | 
						|
	 * truncation has an effect there as well. */
 | 
						|
	memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file));
 | 
						|
	fake_ecryptfs_file.f_path.dentry = dentry;
 | 
						|
	/* Released at out_free: label */
 | 
						|
	ecryptfs_set_file_private(&fake_ecryptfs_file,
 | 
						|
				  kmem_cache_alloc(ecryptfs_file_info_cache,
 | 
						|
						   GFP_KERNEL));
 | 
						|
	if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) {
 | 
						|
		rc = -ENOMEM;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	ecryptfs_set_file_lower(
 | 
						|
		&fake_ecryptfs_file,
 | 
						|
		ecryptfs_inode_to_private(dentry->d_inode)->lower_file);
 | 
						|
	/* Switch on growing or shrinking file */
 | 
						|
	if (new_length > i_size) {
 | 
						|
		char zero[] = { 0x00 };
 | 
						|
 | 
						|
		/* Write a single 0 at the last position of the file;
 | 
						|
		 * this triggers code that will fill in 0's throughout
 | 
						|
		 * the intermediate portion of the previous end of the
 | 
						|
		 * file and the new and of the file */
 | 
						|
		rc = ecryptfs_write(&fake_ecryptfs_file, zero,
 | 
						|
				    (new_length - 1), 1);
 | 
						|
	} else { /* new_length < i_size_read(inode) */
 | 
						|
		/* We're chopping off all the pages down do the page
 | 
						|
		 * in which new_length is located. Fill in the end of
 | 
						|
		 * that page from (new_length & ~PAGE_CACHE_MASK) to
 | 
						|
		 * PAGE_CACHE_SIZE with zeros. */
 | 
						|
		size_t num_zeros = (PAGE_CACHE_SIZE
 | 
						|
				    - (new_length & ~PAGE_CACHE_MASK));
 | 
						|
 | 
						|
		if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
 | 
						|
			rc = vmtruncate(inode, new_length);
 | 
						|
			if (rc)
 | 
						|
				goto out_free;
 | 
						|
			rc = vmtruncate(lower_dentry->d_inode, new_length);
 | 
						|
			goto out_free;
 | 
						|
		}
 | 
						|
		if (num_zeros) {
 | 
						|
			char *zeros_virt;
 | 
						|
 | 
						|
			zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
 | 
						|
			if (!zeros_virt) {
 | 
						|
				rc = -ENOMEM;
 | 
						|
				goto out_free;
 | 
						|
			}
 | 
						|
			rc = ecryptfs_write(&fake_ecryptfs_file, zeros_virt,
 | 
						|
					    new_length, num_zeros);
 | 
						|
			kfree(zeros_virt);
 | 
						|
			if (rc) {
 | 
						|
				printk(KERN_ERR "Error attempting to zero out "
 | 
						|
				       "the remainder of the end page on "
 | 
						|
				       "reducing truncate; rc = [%d]\n", rc);
 | 
						|
				goto out_free;
 | 
						|
			}
 | 
						|
		}
 | 
						|
		vmtruncate(inode, new_length);
 | 
						|
		rc = ecryptfs_write_inode_size_to_metadata(inode);
 | 
						|
		if (rc) {
 | 
						|
			printk(KERN_ERR	"Problem with "
 | 
						|
			       "ecryptfs_write_inode_size_to_metadata; "
 | 
						|
			       "rc = [%d]\n", rc);
 | 
						|
			goto out_free;
 | 
						|
		}
 | 
						|
		/* We are reducing the size of the ecryptfs file, and need to
 | 
						|
		 * know if we need to reduce the size of the lower file. */
 | 
						|
		lower_size_before_truncate =
 | 
						|
		    upper_size_to_lower_size(crypt_stat, i_size);
 | 
						|
		lower_size_after_truncate =
 | 
						|
		    upper_size_to_lower_size(crypt_stat, new_length);
 | 
						|
		if (lower_size_after_truncate < lower_size_before_truncate)
 | 
						|
			vmtruncate(lower_dentry->d_inode,
 | 
						|
				   lower_size_after_truncate);
 | 
						|
	}
 | 
						|
out_free:
 | 
						|
	if (ecryptfs_file_to_private(&fake_ecryptfs_file))
 | 
						|
		kmem_cache_free(ecryptfs_file_info_cache,
 | 
						|
				ecryptfs_file_to_private(&fake_ecryptfs_file));
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
ecryptfs_permission(struct inode *inode, int mask)
 | 
						|
{
 | 
						|
	return inode_permission(ecryptfs_inode_to_lower(inode), mask);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * ecryptfs_setattr
 | 
						|
 * @dentry: dentry handle to the inode to modify
 | 
						|
 * @ia: Structure with flags of what to change and values
 | 
						|
 *
 | 
						|
 * Updates the metadata of an inode. If the update is to the size
 | 
						|
 * i.e. truncation, then ecryptfs_truncate will handle the size modification
 | 
						|
 * of both the ecryptfs inode and the lower inode.
 | 
						|
 *
 | 
						|
 * All other metadata changes will be passed right to the lower filesystem,
 | 
						|
 * and we will just update our inode to look like the lower.
 | 
						|
 */
 | 
						|
static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
 | 
						|
{
 | 
						|
	int rc = 0;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
	struct inode *inode;
 | 
						|
	struct inode *lower_inode;
 | 
						|
	struct ecryptfs_crypt_stat *crypt_stat;
 | 
						|
 | 
						|
	crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
 | 
						|
	if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
 | 
						|
		ecryptfs_init_crypt_stat(crypt_stat);
 | 
						|
	inode = dentry->d_inode;
 | 
						|
	lower_inode = ecryptfs_inode_to_lower(inode);
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	mutex_lock(&crypt_stat->cs_mutex);
 | 
						|
	if (S_ISDIR(dentry->d_inode->i_mode))
 | 
						|
		crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
 | 
						|
	else if (S_ISREG(dentry->d_inode->i_mode)
 | 
						|
		 && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
 | 
						|
		     || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
 | 
						|
		struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 | 
						|
 | 
						|
		mount_crypt_stat = &ecryptfs_superblock_to_private(
 | 
						|
			dentry->d_sb)->mount_crypt_stat;
 | 
						|
		rc = ecryptfs_read_metadata(dentry);
 | 
						|
		if (rc) {
 | 
						|
			if (!(mount_crypt_stat->flags
 | 
						|
			      & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
 | 
						|
				rc = -EIO;
 | 
						|
				printk(KERN_WARNING "Either the lower file "
 | 
						|
				       "is not in a valid eCryptfs format, "
 | 
						|
				       "or the key could not be retrieved. "
 | 
						|
				       "Plaintext passthrough mode is not "
 | 
						|
				       "enabled; returning -EIO\n");
 | 
						|
				mutex_unlock(&crypt_stat->cs_mutex);
 | 
						|
				goto out;
 | 
						|
			}
 | 
						|
			rc = 0;
 | 
						|
			crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
 | 
						|
		}
 | 
						|
	}
 | 
						|
	mutex_unlock(&crypt_stat->cs_mutex);
 | 
						|
	if (ia->ia_valid & ATTR_SIZE) {
 | 
						|
		ecryptfs_printk(KERN_DEBUG,
 | 
						|
				"ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n",
 | 
						|
				ia->ia_valid, ATTR_SIZE);
 | 
						|
		rc = ecryptfs_truncate(dentry, ia->ia_size);
 | 
						|
		/* ecryptfs_truncate handles resizing of the lower file */
 | 
						|
		ia->ia_valid &= ~ATTR_SIZE;
 | 
						|
		ecryptfs_printk(KERN_DEBUG, "ia->ia_valid = [%x]\n",
 | 
						|
				ia->ia_valid);
 | 
						|
		if (rc < 0)
 | 
						|
			goto out;
 | 
						|
	}
 | 
						|
 | 
						|
	/*
 | 
						|
	 * mode change is for clearing setuid/setgid bits. Allow lower fs
 | 
						|
	 * to interpret this in its own way.
 | 
						|
	 */
 | 
						|
	if (ia->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
 | 
						|
		ia->ia_valid &= ~ATTR_MODE;
 | 
						|
 | 
						|
	mutex_lock(&lower_dentry->d_inode->i_mutex);
 | 
						|
	rc = notify_change(lower_dentry, ia);
 | 
						|
	mutex_unlock(&lower_dentry->d_inode->i_mutex);
 | 
						|
out:
 | 
						|
	fsstack_copy_attr_all(inode, lower_inode, NULL);
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 | 
						|
		     struct kstat *stat)
 | 
						|
{
 | 
						|
	struct kstat lower_stat;
 | 
						|
	int rc;
 | 
						|
 | 
						|
	rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry),
 | 
						|
			 ecryptfs_dentry_to_lower(dentry), &lower_stat);
 | 
						|
	if (!rc) {
 | 
						|
		generic_fillattr(dentry->d_inode, stat);
 | 
						|
		stat->blocks = lower_stat.blocks;
 | 
						|
	}
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
int
 | 
						|
ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 | 
						|
		  size_t size, int flags)
 | 
						|
{
 | 
						|
	int rc = 0;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	if (!lower_dentry->d_inode->i_op->setxattr) {
 | 
						|
		rc = -ENOSYS;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	mutex_lock(&lower_dentry->d_inode->i_mutex);
 | 
						|
	rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value,
 | 
						|
						   size, flags);
 | 
						|
	mutex_unlock(&lower_dentry->d_inode->i_mutex);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
ssize_t
 | 
						|
ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
 | 
						|
			void *value, size_t size)
 | 
						|
{
 | 
						|
	int rc = 0;
 | 
						|
 | 
						|
	if (!lower_dentry->d_inode->i_op->getxattr) {
 | 
						|
		rc = -ENOSYS;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	mutex_lock(&lower_dentry->d_inode->i_mutex);
 | 
						|
	rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
 | 
						|
						   size);
 | 
						|
	mutex_unlock(&lower_dentry->d_inode->i_mutex);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static ssize_t
 | 
						|
ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
 | 
						|
		  size_t size)
 | 
						|
{
 | 
						|
	return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
 | 
						|
				       value, size);
 | 
						|
}
 | 
						|
 | 
						|
static ssize_t
 | 
						|
ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
 | 
						|
{
 | 
						|
	int rc = 0;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	if (!lower_dentry->d_inode->i_op->listxattr) {
 | 
						|
		rc = -ENOSYS;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	mutex_lock(&lower_dentry->d_inode->i_mutex);
 | 
						|
	rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
 | 
						|
	mutex_unlock(&lower_dentry->d_inode->i_mutex);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
 | 
						|
{
 | 
						|
	int rc = 0;
 | 
						|
	struct dentry *lower_dentry;
 | 
						|
 | 
						|
	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 | 
						|
	if (!lower_dentry->d_inode->i_op->removexattr) {
 | 
						|
		rc = -ENOSYS;
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
	mutex_lock(&lower_dentry->d_inode->i_mutex);
 | 
						|
	rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
 | 
						|
	mutex_unlock(&lower_dentry->d_inode->i_mutex);
 | 
						|
out:
 | 
						|
	return rc;
 | 
						|
}
 | 
						|
 | 
						|
int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
 | 
						|
{
 | 
						|
	if ((ecryptfs_inode_to_lower(inode)
 | 
						|
	     == (struct inode *)candidate_lower_inode))
 | 
						|
		return 1;
 | 
						|
	else
 | 
						|
		return 0;
 | 
						|
}
 | 
						|
 | 
						|
int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
 | 
						|
{
 | 
						|
	ecryptfs_init_inode(inode, (struct inode *)lower_inode);
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
const struct inode_operations ecryptfs_symlink_iops = {
 | 
						|
	.readlink = ecryptfs_readlink,
 | 
						|
	.follow_link = ecryptfs_follow_link,
 | 
						|
	.put_link = ecryptfs_put_link,
 | 
						|
	.permission = ecryptfs_permission,
 | 
						|
	.setattr = ecryptfs_setattr,
 | 
						|
	.setxattr = ecryptfs_setxattr,
 | 
						|
	.getxattr = ecryptfs_getxattr,
 | 
						|
	.listxattr = ecryptfs_listxattr,
 | 
						|
	.removexattr = ecryptfs_removexattr
 | 
						|
};
 | 
						|
 | 
						|
const struct inode_operations ecryptfs_dir_iops = {
 | 
						|
	.create = ecryptfs_create,
 | 
						|
	.lookup = ecryptfs_lookup,
 | 
						|
	.link = ecryptfs_link,
 | 
						|
	.unlink = ecryptfs_unlink,
 | 
						|
	.symlink = ecryptfs_symlink,
 | 
						|
	.mkdir = ecryptfs_mkdir,
 | 
						|
	.rmdir = ecryptfs_rmdir,
 | 
						|
	.mknod = ecryptfs_mknod,
 | 
						|
	.rename = ecryptfs_rename,
 | 
						|
	.permission = ecryptfs_permission,
 | 
						|
	.setattr = ecryptfs_setattr,
 | 
						|
	.setxattr = ecryptfs_setxattr,
 | 
						|
	.getxattr = ecryptfs_getxattr,
 | 
						|
	.listxattr = ecryptfs_listxattr,
 | 
						|
	.removexattr = ecryptfs_removexattr
 | 
						|
};
 | 
						|
 | 
						|
const struct inode_operations ecryptfs_main_iops = {
 | 
						|
	.permission = ecryptfs_permission,
 | 
						|
	.setattr = ecryptfs_setattr,
 | 
						|
	.getattr = ecryptfs_getattr,
 | 
						|
	.setxattr = ecryptfs_setxattr,
 | 
						|
	.getxattr = ecryptfs_getxattr,
 | 
						|
	.listxattr = ecryptfs_listxattr,
 | 
						|
	.removexattr = ecryptfs_removexattr
 | 
						|
};
 |